<?php
/**
 * CBaseUserIdentity class file
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.yiiframework.com/
 * @copyright 2008-2013 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

/**
 * CBaseUserIdentity is a base class implementing {@link IUserIdentity}.
 *
 * CBaseUserIdentity implements the scheme for representing identity
 * information that needs to be persisted. It also provides the way
 * to represent the authentication errors.
 *
 * Derived classes should implement {@link IUserIdentity::authenticate}
 * and {@link IUserIdentity::getId} that are required by the {@link IUserIdentity}
 * interface.
 *
 * @property mixed $id A value that uniquely represents the identity (e.g. primary key value).
 * The default implementation simply returns {@link name}.
 * @property string $name The display name for the identity.
 * The default implementation simply returns empty string.
 * @property array $persistentStates The identity states that should be persisted.
 * @property boolean $isAuthenticated Whether the authentication is successful.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @package system.web.auth
 * @since 1.0
 */
abstract class CBaseUserIdentity extends CComponent implements IUserIdentity
{
    const ERROR_NONE = 0;
    const ERROR_USERNAME_INVALID = 1;
    const ERROR_PASSWORD_INVALID = 2;
    const ERROR_UNKNOWN_IDENTITY = 100;

    /**
     * @var integer the authentication error code. If there is an error, the error code will be non-zero.
     * Defaults to 100, meaning unknown identity. Calling {@link authenticate} will change this value.
     */
    public $errorCode = self::ERROR_UNKNOWN_IDENTITY;
    /**
     * @var string the authentication error message. Defaults to empty.
     */
    public $errorMessage = '';

    private $_state = array();

    /**
     * Returns a value that uniquely represents the identity.
     * @return mixed a value that uniquely represents the identity (e.g. primary key value).
     * The default implementation simply returns {@link name}.
     */
    public function getId()
    {
        return $this->getName();
    }

    /**
     * Returns the display name for the identity (e.g. username).
     * @return string the display name for the identity.
     * The default implementation simply returns empty string.
     */
    public function getName()
    {
        return '';
    }

    /**
     * Returns the identity states that should be persisted.
     * This method is required by {@link IUserIdentity}.
     * @return array the identity states that should be persisted.
     */
    public function getPersistentStates()
    {
        return $this->_state;
    }

    /**
     * Sets an array of persistent states.
     *
     * @param array $states the identity states that should be persisted.
     */
    public function setPersistentStates($states)
    {
        $this->_state = $states;
    }

    /**
     * Returns a value indicating whether the identity is authenticated.
     * This method is required by {@link IUserIdentity}.
     * @return boolean whether the authentication is successful.
     */
    public function getIsAuthenticated()
    {
        return $this->errorCode == self::ERROR_NONE;
    }

    /**
     * Gets the persisted state by the specified name.
     * @param string $name the name of the state
     * @param mixed $defaultValue the default value to be returned if the named state does not exist
     * @return mixed the value of the named state
     */
    public function getState($name, $defaultValue = null)
    {
        return isset($this->_state[$name]) ? $this->_state[$name] : $defaultValue;
    }

    /**
     * Sets the named state with a given value.
     * @param string $name the name of the state
     * @param mixed $value the value of the named state
     */
    public function setState($name, $value)
    {
        $this->_state[$name] = $value;
    }

    /**
     * Removes the specified state.
     * @param string $name the name of the state
     */
    public function clearState($name)
    {
        unset($this->_state[$name]);
    }
}
